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1.
抗人TNF-α单抗基因的克隆及鉴定   总被引:3,自引:0,他引:3  
目的克隆抗人TNF-α鼠单抗得可变区基因以构建人-鼠嵌合抗体表达载体。方法采用RT-PCR技术,以前导肽序列的引物从1个分泌抗人TNF-α的鼠单抗杂交瘤细胞系中克隆抗体轻链、重链可变区基因(Vκ,VH),在大肠杆菌中表达Fab段核实其功能活性。结果分别得到了2个Vκ和2个VH基因。DNA序列测定表明,其中1个轻链可变区基因为骨髓瘤细胞系中固有的无功能基因。1个重链可变区基因经原核系统表达测活表明无抗体活性。另一个轻链和重链可变区基因的成熟蛋白编码部分与从第一骨架区引物所克隆的、可在大肠杆菌表达出抗体活性的Vκ、VH序列相符。将该轻链、重链基因分别克隆到了人-鼠嵌合轻链、重链表达载体中。结论通过原核表达系统核实,获得了抗TNF-α单抗的可变区基因  相似文献   

2.
抗胃癌鼠单抗3H11V区基因的克隆及人—鼠嵌合轻链的表达   总被引:7,自引:0,他引:7  
利用前导肽序列设计引物,采用RT-PCR技术从分泌抗人胃癌的单抗杂交瘤细胞系3H11分离克隆了抗体的轻重链可变区基因序列。经DNA序列分析表明所获基因含有全部前导序列,其成熟蛋白编码部分与从第一骨架区引物所克隆的序列相符。将轻链基因组建到人-鼠嵌合轻链表达载体中,转染至小鼠骨髓瘤细胞Sp2/0中,可获得人鼠嵌合轻链的表达,证明所克隆的基因具有表达活性,为人-鼠嵌合抗体的构建奠定了基础。  相似文献   

3.
研究解决分泌人单抗的杂交瘤细胞系难于稳定持久分泌抗体的难题,制备单链抗体,使单抗分子小型化,为进一步研究其在肿瘤诊断和治疗中的应用作准备。从分泌抗乳腺癌人单抗的杂交瘤细胞CM-1总RNA中,利用RT-PCR技术分别扩增出人单抗重链可变区VH基因和轻链可变区VL基因,将扩增产物纯化后克隆于pGEM-T载体中,进行DNA测序和序列比较分析后,将两者共克隆于表达载体中诱导表达,利用斑点免疫印迹及竞争抑制法检测表达产物的抗原性。所克隆的CM-1人单抗重链可变区和轻链可变区基因片段,分别属于人免疫球蛋白IgM Ⅲ亚群,和鼠κ轻链V亚群,ⅩⅦ家族,用斑点免疫印迹法检测可见表达产物能与人乳腺癌细胞特异结合;人CM-1单克隆抗体对此单链抗体与人乳腺癌细胞的结合有竞争性抑制作用,抑制率为75.7%。结论:成功地制备了可特异结合乳腺癌细胞的CM-1单链抗体。  相似文献   

4.
从分泌鼠抗人CD86单克隆抗体的杂交瘤细胞株(克隆号:1D1)中抽提总RNA,采用简并引物,经RT-PCR扩增单抗VH和VL的DNA编码区基因。通过SMART-PCR扩增VH和VL基因相应的信号肽序列。采用基因重组技术,将单抗VH、VL基因及其相应信号肽序列,与人IgG1的CH基因、Cκ链基因进行拼接,构建人-鼠嵌合抗体基因的表达质粒pIRES/1D1。转染293T细胞进行瞬时表达,采用流式细胞术分析,转染上清与L929-CD86基因转染细胞的阳性结合率为97.6%。既而转染CHO细胞,经G418筛选,获取稳定分泌嵌合抗体的基因转染细胞株(CHO-ch1D1)。收集无血清培养基的培养上清,采用Protein G亲和层析柱分离纯化,经Lowr法定量。从上清中获取的嵌合抗体蛋白的得率为3.066 mg/L。经进一步间接免疫荧光及流式细胞术分析,纯化嵌合抗体与L929-CD86基因转染细胞,及Daudi细胞膜型CD86分子的阳性结合率分别为98.5%和95.7%。将嵌合抗体(终浓度为5μg/ml)加入到Daudi细胞的培养体系中,经显微镜观察及MTT法分析,嵌合抗体对Daudi细胞的生长具有抑制作用(P<0.05)。本研究获取的嵌合抗体在CD86分子的基础和应用研究中具有重要的价值。  相似文献   

5.
目的:通过基因工程抗体改造获得具有与人小细胞肺癌有特异性反应的人-鼠嵌合抗体2F7 Fab片段,方法:采用RT-PCR技术从抗人小细胞肺癌单克隆抗体2F7杂交瘤中克隆该抗体的重,轻链可变区基因,将2F7单抗的重,轻链可变区基因装入带有人恒定区基因的表达载体pSW1-Fab中,构建得到pSW1-2F7 Fab,转化受体菌E.coil XL1-Blue,IPTG诱导表达,经Western blot和ELISA鉴定表达蛋白的活性。结果:从抗人小细胞肺癌单克隆抗体2F7杂交瘤中克隆获得了抗体重、轻链可变区基因,测序证实2F7单抗的重链(VH)可变区基因全长362bp,编码120个氨基酸,轻链(VL)可变区基因全长319bp,编码105个氨基酸,构建的2F7人-鼠嵌合Fab表达载体诱导后获得了目的蛋白的表达,主要分泌在菌液的上清中,表达量较高且稳定,具有与NCI-H128细胞特异性结合的活性。结论:构建和表达了抗人小细胞肺癌单抗2F7人-鼠嵌合Fab片段,表达产物具有与抗原结合的特异性,为进一步研究和应用打下了基础。  相似文献   

6.
利用抗乙肝表面抗原的单抗2H1的轻链可变区基因的一部分,以核酸定点突变法引入MluI限制性内切酶识别位点,构建了含有启动子、前导肽序列以及剪接供体信号等真核表达元件和“EcoRV-Mlu I”外显子克隆“匣”的通用的抗体轻链可变区基因真核表达框架pGEM-LPCR。从分泌CD3单抗的杂交瘤细胞中提取基因组DNA,通过PCR扩增及序列分析证实获得了CD3单抗轻链可变区基因的外显子。将其克隆到pGEM-LPCR中,切下完整的真核转录单位,与带有人Kappa链恒定区基因及选择标记基因的表达载体相连接,成功地构建了抗CD3鼠/人嵌合轻链基因。此表达框架可用于多种抗体轻链可变区基因外显子的克隆及其真核转录单位的制备,大大简化了基因工程抗体的研制。  相似文献   

7.
目的:构建嵌合型抗人黑色素瘤抗体的真核表达载体,并实现真核表达。方法:从3株杂交瘤细胞中克隆得到鼠源单抗的可变区基因,插入含有抗人Tac抗原信号肽以及人免疫球蛋白κ轻链恒定区基因和γ1重链恒定区基因的真核表达载体pMH-CA中,转染293T细胞,进行嵌合抗体表达,并用RT-PCR、ELISA、Westem blot免疫印迹等对抗体表达鉴定。结果:成功构建了抗人黑色素瘤人,鼠嵌合抗体,并实现其真核表达。RT-PCR证实了该抗体在mRNA水平上的表达,ELISA和Westemblot证实了抗人黑色素瘤人,鼠嵌合抗体的表达。结论:成功表达了抗人黑色素瘤人-鼠嵌合抗体。  相似文献   

8.
3B9(杂交瘤细胞)是一株分泌HBV Pre S2抗原的单抗细胞,为从分子水平分析、了解3B9株进而为制备新一代基因工程抗体奠定基础,用分子生物学技术,提取3B9杂交瘤细胞总RNA,经反转录、PCR分离获得了3B9单抗的轻、重链可变区基因,并利用PCR及双脱氧核苷酸链末端终止法对3B9单抗的可变区基因的核苷酸序列进行了分析。结果表明,3B9单抗轻链隶属小鼠Ig Kappa轻链第Ⅱ亚组,JK_1基因重排;而3B9单抗重链隶属小鼠Ⅰg重链第Ⅱc亚组。在此基础上,作者用一编码疏水性多肽接头的DNA片断将3B9单抗轻、重链可变区基因连接,成功地构建了3B9单抗单链可变区抗体基因。为下一步克隆、表达有抗原结合活性的单链抗体打下了良好的物质基础。  相似文献   

9.
目的:制备抗CD4人-鼠嵌合抗体。方法:从分泌抗CD4单克隆抗体的杂交瘤细胞中提取总RNA,通过RT-PCR扩增出VH和VL的DNA 片优,对VH和VL进行DNA序列测定和分析,证实VH和VL具有小鼠Ig可变区完整的结构功能后,将VH亚克隆至重链表达载体pγ1-Expr,VL亚克隆至轻链表达载体pκ-Expr转化XL2-Blue细菌,通过菌落或质粒PCR筛选阳性克隆,通过电转染将VH-Pγ1,LV-pκ共转染至小鼠骨髓瘤细胞X63Ag8,653,通过G418筛选,ELISA和免疫荧光鉴定。结果:得到分泌抗CD4人-鼠嵌合体的阳性转染瘤细胞克隆。所得到的嵌合抗体在体外对PHA和IL-2诱导的PBMC增殖具有抑制作用。结论:人-鼠嵌合抗体得到成功表达,并有可能作为免疫抑制剂应用于抗移植排斥和自身免疫疾病的治疗。  相似文献   

10.
李彪  吴祥甫 《现代免疫学》1998,18(5):262-266
本文采用杆状病毒表达系统在昆虫细胞(Sf_9,秋粘虫细胞)中表达了抗癌胚抗原(CEA)鼠-人嵌合抗体重、轻链基因.将鼠源性单抗杂交瘤细胞中已克隆到的重、轻链可变区(V_H、Vk)基因分别与人免疫球蛋白恒定区基因Cr_3、Ck相拼接,构建鼠人嵌合抗体基因.含嵌合抗体基因的转移载体与线性化病毒DNA共转染Sf_9细胞,并通过点杂交、PCR扩增和Southern blot分析获得重组病毒.Western blot分析表明以重组病毒感染的Sf_9细胞分别表达了嵌合重链和轻链,放射免疫分析法(RIA)和间接ELISA测定的结果表明嵌合重、轻链基因表达产物具有与CEA结合的能力.  相似文献   

11.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

12.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
15.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

16.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

17.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

18.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

19.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

20.
Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten.  相似文献   

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